The invention discloses a preparation method of microwave vacuum puffing pumpkin chips. Fresh pumpkin serves as the main raw material and is prepared into pumpkin chip leisure instant food by cleaning, removing bladder, cutting into blocks, pulping, burdening, cooking, cooling, shaping, microwave vacuum puffing and packaging. The technical scheme of the invention is characterized by introducing in the microwave vacuum puffing technology and effectively reserving the original color, fragrance, taste, nutrition and active ingredients of pumpkin by two stages of microwave vacuum drying. The product is nice and crunchy, contains low grease and low sugar content and has the characteristics of mellow taste, abundant nutrition and active ingredients and long shelf life, is safe and sanitary. Thepreparation method has short processing time, low energy consumption and easy popularization and application. The preparation process of the invention does not add pigments, essence and preservative and is a natural nutrition and health leisure food.